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By Clyde M. Pearce

The Lake Superior iron-mining district includes parts of the States of Michigan, Minnesota, and Wisconsin. The laws of each State provide for an industrial commission and for inspection of mines. The following extract from the General Orders on Mines, effective October 25, 1937, issued by the Industrial Commission of Wisconsin, is the only reference to the use of safety catches on mine cages or skips found in the laws and regulations in the Lake Superior iron-mining district: Order 316 - Cages for Hoisting Men. (c) Sides, Gates, and Safety Catches. ***Every cage shall be provided with safety catches of sufficient strength to hold the cage with its maximum load at any point in the event the hoisting cable should break. (d) Testing Safety Catches. The safety catches of cages and skips used to hoist men shall be kept well oiled and in good working order. They shall be tested at least once each month by tying up the cage or skip with hemp rope, lowering a few feet of hoisting cable on top of cage, then cutting the hemp rope, provided that any other system of testing, which is equally effective, may be used.

Jan 1, 1945

By L. Alan Weakly

The first all-hydraulic drill introduced in the US began test drilling in a Missouri under round lead mine in mid-1973. Since that time, the hydraulic drill concept has slowly, and sometimes haltingly, come of age. Now, backed by impressive performance records and operator acceptance, hydraulic drills promise to produce a quantum leap in mining efficiency and, sometimes, major changes in mine and quarry engineering.

Jan 10, 1979

By R. E. Reed, C. J. McHargue

Poly crystalline aluminum specimens having random and diffuse (001) initial orientations were reduced 90 pct in area at room temperature by drawing, extruding, and swaging. Although each procedure produced the duplex (001)- (111) texture, there were marked dqferences in the relative amounts of each component. This also produced variations in the tensile properties of the aluminum rods. It is generally agreed that the fiber texture found in aluminum rods consists of a strong (111) and a weak (001) component after reductions in area of 90 pct or more. An examination of data summarized in recent reviews'-3 shows much spread in the values for the relative amounts of the two components reported by different investigators. That the initial orientation has a marked influence on the final texture even after reductions in area greater than 90 pct is well-documented.4-7 Another factor which may influence the relative amounts of the two components is the method of fabricating the wires or rods. Barrett and ~assalski' state that the center of wires formed by rolling, swaging, and drawing have the same textures. The data cited in support of this conclusion came from qualitative X-ray techniques. In recent years there has been renewed interest in correlating the type of preferred orientation with such parameters as stacking fault energy and onset of mechanical twinning.'' Since these analyses have often used many sources of data, it is essential that the data be evaluated for the effect of fabrication variables. In this study we have produced aluminum rods by drawing, swaging, and extruding and have quantitatively determined their textures. All specimens had the same purity and fabrication temperature, and the amount of deformation and the starting textures were determined. We have compared our results with published studies on similar materials and fabricating parameters. We have also compared results from the same three fabricating procedures for single-crystal specimens in three instances. EXPERIMENTAL PROCEDURE The aluminum was 99.99+ pct with the only detected impurities being (by weight) 0.002 pct Cu, 0.001 pct Si, and 0.001 pct Mg. Cylinders a in. in diam by 1 in. long with a fine-grain random texture were made by the following method. Cubes 1+ in. on a side were machined from 2-in.-diam ingots. These cubes were slowly pressed about 30 pct in each of the cube directions. The material was recrystallized by annealing 1 hr at 350°C. Three deformation-anneal cycles produced the desired material. Polycrystalline specimens with a diffuse (001) texture were made by casting into a graphite tube 1 in. ID, li in. OD, by 8 in. long which had been preheated to 900°C. One end of the tube was placed on a water-

Jan 1, 1969

By John H. Paugh

Hydraulic slurrying and pumpability characteristics of phosphate matrix (ore) have not been quantitatively defined. An elemental triangular diagram analysis of rock/sediment texture is used to classify the nature of the ore; then related to empirical field data of hydraulic pressureand production yardage ratios. This experiment is applied as a geotechnical tool to provide empirical data of ore slurry and pumpability characteristics as key considerations in the design of slurry pipeline systems. A real texture variability maps are developed on a section of land to assist mine engineering planning.

Jan 1, 1981

By Larissa Agrizzi Ronqueti

The effect of coiling temperature on selective oxidation behaviour of binary and ternary iron-based model alloys containing different contents of Si or Mn were investigated by SEM and SIMS. The experiments were carried out with a temperature ranging from 450 °C to 700 °C, under N2-5%H2 gas flow with a Dew Point of -3.3°C, for different durations. SEM images of binary iron-based model alloys revealed a decrease of grain boundary oxidation depth with increasing Silicon or Manganese content. At 530°C and 600°C SIMS results showed no Silicon diffusion toward surface, contrary to the results analyzed for Fe-x%Mn. Tests results and Wagner’s theory application (specific cases Fe-0.2%Si and Fe-0.5%Si) showed that grain boundary oxygen diffusion coefficient “DoGB” is almost 60 to 70 times faster than oxygen bulk diffusion coefficient. These results helped to broaden knowledge of single-element effects on grain boundary oxidation, in addition, will contribute of the future works in new steels with complex alloy compositions.

Aug 17, 2017

By Rodrigo Rangel Porcaro

Desenvolveu-se um dispositivo para soldagem por gravidade com eletrodos revestidos e investigou-se o comportamento do dispositivo em função de variações nas condições operacionais. Ciclos térmicos durante a deposição de cordões em tubos de aço API X65Q foram avaliados por meio de medidas experimentais, utilizando-se termopares inseridos na poça de fusão durante a soldagem por gravidade. Amostras do metal base e do cordão depositado em diferentes condições de aporte térmico passaram por análise química, microestrutural e metalográfica. Observou-se boa repetibilidade na velocidade de deposição do dispositivo e aspecto visual adequado de cordões de solda depositados. Os resultados dos ciclos térmicos mostram que as variações nos valores de ?t800/500, utilizando eletrodos AWS E7018 e correntes de soldagem de 70A e 150A, causaram redução de 21% na proporção de ferrita acicular e, consequente, redução de 22% nos valores de microdureza do metal de solda com maior aporte térmico.

Oct 30, 2017

By Eric B. Braun

"The paper describes Rio Blanco like a virgin porphyry copper discovery, located in Perú along the Ecuador border at the north end of a belt of copper systems that includes porphyry Cu-Mo, porphyry Cu-Au and highsulfidation types.Rio Blanco is a porphyry Cu-Mo system containing low Au and As. The presence of andalusite, diaspore and pyrophyllite, intense QSP alteration and absence of potassic alteration indicate a shallow level oferosional exposure."

Apr 26, 1999

By Edward L. Clark

The year 1954 witnessed great activity in the field of geology as applied to mining. The search for in nearly all districts is becoming more and more intensified as established reserves are being depleted. Much geologic work has been directed to finding extensions of known orebodies, but prospecting in new areas has constituted a large part of the program of many operators. The acute need for additional reserves has brought into the search all the tools known to the geologic profession. This is reflected directly by frequent references to geophysical and geochemical methods in the regional reviews that follow. The lone prospector of the early days of metal mining has been eliminated almost completely by modern scientific methods involving surface and subsurface geology, exploratory drilling, geophysics, and geochemistry. Nearly all new exploration is based on long-range programs coupled with studies of regional geology to determine the structural environment of areas of mineralization. The success of this approach has encouraged new operators in the field of exploration to adopt similar policies. Only in the search for uranium ores is the individual prospector still active, but the familiar picture of the burro heavily loaded with grubstake, gold pan, and pick and shovel has been replaced by the Geiger counter and the scintillometer carried by hand, by truck, or by airplane.

Jan 3, 1955

By Thomas A. Davidson

The Bureau of Mines Helium Field Operations has developed a simple and accurate method for calculating the viscosity of gas mixtures. Only the composition of the mixture and the molecular weights and viscosities of the pure components in the mixture are required. The momentum fraction of a mixture is calculated from the composition. The fluidity is calculated as a quadratic function of the momentum fractions. The efficiency factor for transfer of momentum in collisions between bodies of different masses is derived and used with one empirical constant. The viscosity is the reciprocal of the fluidity. Results of the method are compared with 752 reported viscosities for 40 dilute binary systems at temperatures from -78 to 276.9°C. Using this method the average absolute deviation is 1.29%, the root-mean-square deviation is 1.99%, and the average deviation is -0.84%.

Jan 1, 2010

By Hall T. P, Taylor R. N

Fluid flow in a 1:14 scale water model of the shaft and settler of the Kalgoorlie Nickel flash smelter has been investigated by flow visualisation and numerical modelling. Detailed flow fields through the reaction shaft, settling chamber and uptake are presented for flow rates up to 800 Vm and a number of burner configurations. The predicted flow fields were compared with experimental data obtained from streak photographs and video recordings. The effects of cessation of flow through individual burners and changes in shaft dimensions were also Investigated.

Jan 1, 1992

By Svatopluk Zeman, Zbynek Akstein, Jiri Pachman, Ahmed Elbeih, Marcela Jungova

BCHMX (cis-1,3,4,6-tetranitro-octahydroimidazo-[4,5-d]imidazole or Bicyclo-HMX) was studied as an energetic component of three different plastic explosives based on three matrices: C4 matrix, semtex10 matrix and silicone matrix. The original plastic explosives, Composition C4 - based on RDX (1,3,5-trinitro-1,3,5-triazinane), Semtex 10 explosive based on PETN (pentaerythritoltetranitrate) and plastic RDX-silicone, were included for comparison. Sensitivity and performance parameters were studied.

Jan 1, 2011

The BLEG (Bulk Leach Extractable Gold) technique is a semiquantitative measure of cyanide extractable gold contained in a sample. A 5kg sample is leached in cyanide solution for 24 hours and gold is precipitated out of the pregnant solution using zinc and assayed by AAS. The detection limit is reported as ppb (parts per billion). Telfer is located 1300km north north-east from Perth in the Great Sandy Desert. The climate is one of hot summers with irregular rainfall and mild winters. A large portion of the area is covered by aeolian sand and seif dunes with poorly developed drainage, rare outcrop; topographic relief is a maximum of 96m. Poor outcrop and poorly developed drainage render conventional stream sediment sampling and soil geochemistry inadequate. Therefore a technique providing a minimum number of samples with maximum accuracy and sensitivity was needed. Consequently BLEG orientation surveys were conducted over the Telfer Mine area in 1983, 1984 and 1985.

Jan 1, 1988

By H. H. Schrenk, L. B. Berger, W. P. Yant, F. A. Patty

"The use of small such as canaries and white mice, for detecting carbon monoxide depends primarily on the fact that the volume of respiration of these animals in proportion to their volume of blood is much higher than for man. Accordingly, when animals and men are simultaneously exposed to a given concentration of carbon monoxide the animals will absorb it more rapidly and attain serious poisoning in less time than men. Prom a practical viewpoint the use of the animals depends on the margin of time between observable symptoms in them and serious poisoning in man, during which man can return to fresh air or use respiratory protection. It should be remembered, however, that during the time the animal is incurring a detectable degree of poisoning, man is also absorbing some carbon monoxide, and the margin of time is not very wide. Experience with canaries has shown that an occasional specimen may have a tolerance above the average of the species and fail to exhibit symptoms before man incurs a very discomforting and possibly a serious degree of poisoning.It is also well known that physical activity increases the demand for oxygen by the body, and the respiratory exchange and circulation of the blood are increased to meet the demand. This sets up a vicious condition if carbon monoxide is present in the air because the rate of absorption of carbon monoxide is not only increased by the increase in respiration and circulation, but the absorption of carbon monoxide decreases the capacity of the blood for carrying oxygen at a time when the demand is high. These facts, together with the increase in respiration and circulation which attend excitement, underlie the caution to be calm and to walk slowly and to reduce physical exertion to a minimum when exposed to carbon monoxide. For these same reasons, when using animals for detecting carbon monoxide it is endeavored to keep them active, thereby tending to increase the response of the birds and widen the time between observable effects in the birds and effects in the man. As rule canaries are kept fairly active through fright at the unnatural surroundings and in their endeavor to remain on the perch of the cage when carried into the atmosphere to be examined. They also experience an excitement stage with oncoming carbon monoxide poisoning. Sometimes, however, especially if the air is cold, they tend to be inactive and quiet. Ordinary mice and white mice become inactive with use and also with oncoming poisoning. They huddle in the corner or the cage, and thereby not only reduce their sensitivity but make it difficult to observe signs of poisoning."

Oct 1, 1930

By Felicia F. Peng

A laboratory fixed bed reactor was used in a study of generating clean thermal energy from coal fine refuse-limestone agglomerates. The major operation variables, including Ca/S mole ratio, agglomerate size, air flow rate and temperature, which affect the rate of sulfur fixation and combustible material utilization, have been examined. The test results show that 70 percent or more of sulfur fixation and 100% of combustible material utilization can be achieved depending upon sorbent, agglomeration, and combustion conditions. The coal fine refuse limestone pellet combustion process (CLC process) requires a simple flowsheet to convert coal fine refuse as a clean solid fuel, while meeting the strict air quality standards for SO2 emissions into the atmosphere. The CLC process is an attractive method to clean up coal slurry impoundments to protect our environment.

Jan 1, 1984

By R. J. Sandrea, S. M. Farouq Ali

The results of an experimental and theoretical study of the effects of rectilinear impermeable barriers and highly permeable channels on the sweep efficiency and conductivity of a five-spot network are presented. The study was carried out using Hele-Shaw, and conductive sheet analogs for both. normal and inverted flood patterns. A functional relationship was developed which provides quantitative prediction of the above parameters; i.e., sweep efficiency and conductivity, for the nonhomogeneous system. To evaluate this, it is necessary only to measure the interference modulus of the obstacle using a simple expression. The results indicate that impermeable barriers, with an interference modulus greater than zero, always cause a decrease in the conductivity and the sweep efficiency of the pattern. On the other hand, permeability channels do not have a significant effect on these parameters, unless they are located along the streamlines. The study also discusses a method of formulating the difference equations pertaining to the two-dimensional Laplacian in a system containing rectilinear barriers. In addition, a technique is described for tracing the progress of a free surface, using marked particles, in a stream containing discontinuities SuCh as those occurring at the extremities of barriers. The above computational scheme was used in a digital computer program to simulate results of the Hele-Shaw analog. The computed values of sweep efficiency mere in good agreement with the experimental values. INTRODUCTION At the present time waterflooding remains the most widely used technique for the secondary recovery of oil. Among the numerous factors that affect the performance of a waterflood, the areal sweep efficiency constitutes one of the most critical parameters. It is a function only of the geometric distribution of the wells for a homogeneous medium and unit mobility ratio. Geological considerations, however, such as the presence of sealing faults or solution channels in the rock matrix, would generally exert an adverse effect on the areal sweep efficiency of a waterflood network. Surprisingly little information is presently available on the quantitative implications of such permeability interferences. It was the object of this investigation to consider the presence of rectilinear, impermeable and highly permeable interferences in an otherwise homogeneous five-spot pattern, and to analyze their effects on the resulting sweep efficiency and pattern conductivity. The experimental phase of the study was conducted using two different models: the Hele-Shaw flow cell and the field plotter. For experimental convenience, the geometric boundaries of the five-spot were assumed to constitute streamlines even in the case where the interference was asymmetrically placed with respect to a repeated five-spot pattern. A second object of the study was to develop a computational scheme for numerically calculating the pressure distribution in a five-spot flow pattern containing rectilinear, impermeable barriers, and to use this distribution to compute the sweep efficiency. EXPERIMENTAL PROCEDURE HELE-SHAW ANALOG The Hele-Shaw analog was used both as a visual model and for determining the sweep efficiency for systems involving impermeable barriers. The physical limitations of this model as a means of experimentally studying the motion of a fluid in porous medium have been adequately discussed elsewhere.2,7 Likewise, it can be easily verified that the analogy remains valid when a portion of the region between the plates contains an obstacle of the same thickness as the distance between the plates. The model used in this study was composed of

By C. Villachica

El presente texto refiere la aplicación del carbón activo como reactivo en las soluciones de los procesos de concentración por flotación minera. La justificación de su uso es porque la mayor selectividad del proceso incrementa significativamente las utilidades de la compañía minera. Asimismo, otros usos del carbón activo en estudio, se extienden a la absorción de iones perjudiciales a la flotación, mejoramiento de la flotación bulk, recuperación de espumante y colector, recuperación de finos, mejoramiento de la sedimentación de los concentrados y la recuperación de la plata y oro de los efluentes de la fundición y relaves.

Oct 14, 1980

By J. L. Eakin, J. P. Powell

"The increased costs of exploration and drilling of new oil fields and the continued success of water flooding in nearly depleted oil fields have created a demand for information on the results obtained from individual projects. The Bureau of Mines has published several reports concerning water-flood activity in the Midcontinent area and at the request of the industry has continued to collect and disseminate this information. This report was written in response to these requests. It describes in detail the water-flooding projects in Anderson, Franklin, Linn, and Miami Counties, Kans., and includes methods of water treating and the results obtained. The production histories of each county and many water-flood projects are shown graphically from the date of the first development. Maps of most of the major projects, showing their status as of January 1, 1953 are presented also.The practice of injecting water to stimulate oil production was legalized in Kansas in 1935, and the first water-flooding project authorized in this four-county area was initiated by the Texas Co. in December 1935 in Linn County. Forty-nine projects2/ initiated in the area to January 1953 are estimated to have recovered approximately 10 million barrels of oil that would not have been produced by methods used previously. About 7,900 productive acres had been, or are, flooded by these projects, and approximately 136 million barrels of water had been injected.These four counties in the eastern Kansas shallow production area3/ were an important factor in the early history of the Kansas oil and gas industry. This position has been maintained from the very beginning through the early period of vacuum and air injection and into the era of water flooding. The location of the area and the relative position of the four counties and water-flooding areas in each are shown in figure 1.The first drilling for oil in this area in 1860 resulted from investigations of the existence, and use by the Indians, of so-called tar or oil springs. The first wells drilled were nonproductive, and the impending Civil War caused the search for oil to be discontinued. In 1884 a few shallow oil wells were drilled near Paola, and completion of several gas wells near that city led to subsequent drilling of an oil well, which was completed in June 1885, having an initial flow of 10 barrels of oil daily.In 1904 the original Paola gas field became a good oil-producing field. In 1905 the Rantoul field in Franklin and Miami Counties was opened; and drilling activity spread throughout the adjoining area, resulting in development of several shallow oil pools in Linn and Anderson Counties. The first ""shoestring"" pool in eastern Kansas to produce oil was probably the Paola or Pressonville shoestring, which was discovered in 1917. The rate of oil production from the area declined until 1919, when the Centerville shoestring pool was discovered. Discovery of the Colony gas field in 1921 was followed within a few months by drilling of the Garnett and Garnett and bush City shoestring pools. The Schermerhorn pool (now part of the Centerville field) s discovered in 1927, and the Kincaid shoestring pool was first drilled in 1931. The oil-production histories of the individual counties are discussed separately."

Jun 1, 1953

By V. K. Gupta

A detailed experimental study of the variations in grinding rate with particle size, particle load, ball diameter, ball load, mill diameter, and mill speed was carried out for a soft cement clinker and a hard cement clinker. The effects of the ball diameter, ball load and particle load were observed to be material (hardness) independent, and those of the particle size, mill diameter and mill speed to be material dependent. A sharp change in the grinding behavior was observed for both the clinkers at about 150 µm size. Below this critical size: (i) the hardness difference between the two clinkers became insignificant, (ii) variation in the grinding rate with particle size became markedly more pronounced, and (iii) mill speed had little or no effect on grinding rate. The importance of these results in the context of process optimization and control is discussed.

Jan 1, 1987

By W. E. Miller, G. S. Scott, G. W. Jones

"INTRODUCTION One of the major activities of the Bureau of Mines is the promotion of safety in mining and the mineral industries. Research is undertaken in connection with these problems to determine the explosion and ignition hazards of combustible gases, liquids, and solids and to investigate means of reducing them.Occasionally the Bureau is asked to determine inflammability or ignition temperatures to enhance safety in nonrnineral industries. From time to time it has complied with such requests when no other agency was available to do the work and the investigation could be conducted with a minimum of time and expense. The present investigation is one of this class.Nicotine (C10H14N2), a colorless combustible liquid having a boiling point of 246°C, is usually obtained from tobacco and its products by extraction processes. When heated to its boiling point it decomposes; the purified product is obtained from tobacco extractions by distillation at reduced pressures or is distilled in a current of inert gas.It has an unpleasant odor, a burning taste, and in the undiluted state is highly toxic. Under certain conditions it can be oxidised to nicotinic acid and in the near future may therefore become of considerable economic importance. Nicotinic acid is a component of the vitamin B complex now commonly used to fortify white flour and other foods that normally are deficient in these vitamins."

May 1, 1942

By Hugh R. Rhys

The question of the desirability of recovering cullet from MSW in order to recycle it into the manufacturing of glass containers remains a controversial one. The main factors appear to be: 1. The position of the Glass Container Manufacturers Institute (GCMI), as the trade association for most container manufacturers, is that post-consumer cullet is a vital source of raw material. Present requirements are for: a) Flint cullet b) Non-flint cullet of known mix proportions c) Mixed unsorted cullet of known mix propertions c) Mixed or non-flint cullet of unknown mix proportions. A market balance for these products exists, and this might somewhat limit the outlets for (b), (c) and (d), or severely limit the outlet for (d) alone. 2. The color specifications are rather strict. With cullet admixtures of 20% of the melt or more, and the use of decolorisers in a flint furnace discouraged because their action is reducing in a process which requires an oxidising environment, color contamination in a flint furnace is serious.. For amber and green furnaces (reducing) it is less serious, but in order that the quantity of decolorisers may be controlled, the color balance (as a measure of the Fe and Cr content) of the admixtured cullet should be known. 3. Why not simply color analyze, either by a continuous on-stream or off-stream: photo-electronic analysis, or by systematic batch sampling (with some kind off electronic surveillance of the mainstream) and just send mixed, color measured cullet to only amber and green furnaces? The flint would-be simply included in the mix. This is probably technically feasible, but is subject to the market limitations noted in point1.

Jan 1, 1975